Biology Extra credit worksheet animals

Basic characteristics of animals:

1. Multicellular
   • Diversity of organization of cells, tissues, organs, and organ systems
2. Diversity of modes of locomotion
   • Skeletons, nerves, and muscle tissue
3. Diversity of feeding habits
   • All heterotrophic. Feeding types: Suspension/filter, Deposit, Mass, Fluid.
4. Sexual and asexual reproduction
   • Predominantly diploid (2n), only gametes are haploid (n)

Body Symmetry:

Animal bodies either have:

• No plane of symmetry: asymmetry. Think sponge

• Multiple planes of symmetry: radial symmetry. Think jellyfish
• One plane of symmetry: bilateral symmetry. Think human

Metazoa: monophyletic clade of multicellular animals with tissues and organs. Only metazoans have true tissues.

Body Tissues:

Tissue: specialized groups of cells. Name the 4 tissues:

Germ layer: group of tissues that share a common origin during embryonic development. Germ layer develops into organs and organ systems later in development.

There are 3 germ layers:

1. Ectoderm: Outer layer, which develops into_______________________________________________
2. Mesoderm: Middle layer, which develops into_____________________________________________
3. Endoderm: Innermost layer, which develops into___________________________________________

Diploblastic animals are radially symmetrical have 2 germ layers: _________________ and _________________.

Triploblastic animals are bilaterians have 3 germ layers: ____________________, ____________________, and

____________________.

Triploblastic bilaterians can be split up into 2 monophyletic groups:

1. Protostomes: Mouth produced from first embryo infolding. Examples:_____________________________
2. Deuterostomes: Anus produced from first embryo infolding. Examples:____________________________

Triploblastic bilaterians start to develop a body cavity surrounded by mesoderm!

• Coelom: Enclosed, fluid-filled body cavity formed within mesoderm
• Coelomates: have a fully lined body cavity
• The coelom provides shock absorption for organs because it is filled with fluid AND allows for muscle growth independent from body wall. The evolution of the coelom gave us our complex internal bodies!

Bilaterians developed heads (i.e. cephalization) which lead to: a brain + central nervous system, sensory organs (e.g. eyes), sophisticated musculature, appendages, and segmentation (compartmentalization) of the body. These innovations lead to increased mobility and coordination, specialized feeding techniques and mating abilities.

 Terrestrialization of Animals: Aquatic vertebrates colonized land ~ 360 MYA. This transitional fossil species was a fish/tetrapod hybrid and looked a little bit like a salamander. Below are a list of challenges that animals faced during terrestrialization. Name and describe adaptations that may have helped to address these challenges using the following Word bank: